1. Field of the Invention
The present invention relates to a plasma processing apparatus.
2. Description of the Related Art
Conventionally, in a process of manufacturing a semiconductor device, a plasma processing apparatus for performing various processes, for example, etching or film formation, is used by using plasma on a substrate (for example, a semiconductor wafer) held on a holding stage in a processing chamber. Also, as the plasma processing apparatus, there is known a capacity coupled plasma processing apparatus that includes an upper electrode provided in a ceiling portion of the processing chamber to face the holding stage on which the substrate is placed, and the holding stage as a lower electrode, which constitutes a pair of opposite electrodes.
In the capacity coupled plasma processing apparatus, as high-frequency power applied between the upper electrode and the lower electrode, first high-frequency power for generating plasma and having relatively high frequency and second high-frequency power for dragging ions and having a lower frequency than the frequency of the first high-frequency power are applied to the holding stage as the lower electrode.
Also, there is known a plasma processing apparatus that applies high-frequency power to a lower electrode and applies a direct current voltage to an upper electrode. As such, in the plasma processing apparatus applying a direct current voltage to the upper electrode, as a ground member for a direct current voltage, there is known a ring-shaped member formed of a conductive material, e.g., silicon, provided to be exposed in a processing chamber and to surround a holding stage (for example, refer to Patent Reference 1).
Recently, in a manufacturing field of a semiconductor device, since batch etching of a multi-layered structure has been mainstream, there is a need to perform a plurality of plasma etching processes or the like in a single processing chamber. Accordingly, there is a need to finely control plasma to meet conditions of an individual process.
3. Prior Art Reference
(Patent Reference 1) Japanese Patent Laid-Open Publication No. 2008-251744